This invention relates to Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) methods.
CAD/CAM software systems are long known in the computer art. Some utilize wire-and-frame methods of building models while others utilize form features. In the form feature method of building CAD/CAM models, physical features are added to the model in an associative relationship with whatever other feature they are immediately attached to. The drawback is that the alteration or deletion of any one feature will result in the alteration or deletion of any other features attached to it. This makes altering or correcting complicated models rather time-consuming.
Disclosed herein is a horizontal method of CAD/CAM manufacturing that is novel and superior over the vertical methods of the prior art. The invention permits alterations, additions, and deletions of individual features (e.g., holes, bosses, etc.) of a virtual part, wherein a change in any one feature is independent of the remaining features. The invention may be implemented on any CAD/CAM software package that supports (a) reference planes or their Cartesian equivalents, (b) parametric modeling or its equivalent, and (c) feature modeling or its equivalents.
The invention is to utilize a xe2x80x9chorizontal tree structurexe2x80x9d in adding form features to a model by establishing an exclusive parent/child relationship between a set of reference planes and each form feature. The reference planes themselves are children of a parent base model that may correspond to a real-world part or blank in the manufacturing process of the model. The parent/child relationship means that changes to the parent will affect the child, but changes to the child have no effect upon the parent. Since each added form feature of the model is related exclusively to a reference coordinate, then individual features may be added, edited, suppressed or deleted individually without affecting the rest of the model.
The order of addition of the form features may be controlled by the user and xe2x80x9cextractsxe2x80x9d made of the model each showing an additional step to be performed in the manufacture of the model in accordance with the order. Each extract is in the nature of a xe2x80x9csnapshotxe2x80x9d of the manufactured model in progress that may then be used to generate process sheets or electronic instructions for machining tools to manufacture a real-world version of the CAD/CAM model. The method is novel and superior over prior art xe2x80x9cverticalxe2x80x9d structures wherein changes or deletions to any one feature affect all features connected to that feature.